Gastroplasty ring that can be loosened

ABSTRACT

A gastroplasty ring having a single control is provided and includes a flexible strip with two ends for being closed around the stomach by a closure system so as to reduce the diameter of the opening of the stoma. The strip may have an annular compression chamber of adjustable volume and of substantially constant section connected by an adjustment catheter to a device for adjusting the internal pressure in the chamber so as to adjust its diametral expansion. The closure system may be used for reversibly locking and loosening the ring, and for releasing the diameter of the ring momentarily by relative displacement between the two ends, while continuously forming a closed loop around the stomach. The ring constitutes a gastric implant for treating obesity.

TECHNICAL FIELD

The present invention relates to the technical field of surgicalimplants for treating obesity by implanting a flexible gastric strip forconstricting the stomach of a patient, said gastric strip being providedwith an annular compression chamber of variable volume that isadjustable by means of an adjustment catheter connected to a control andadjustment device implanted in the body of the patient.

The present invention relates to a gastroplasty ring formed by aflexible strip for passing around the stomach and being closedsubstantially near and by means of its two ends, using a closure systemto reduce the diameter of the stoma opening, said strip including anannular compression chamber of adjustable volume that is connected by anadjustment catheter to a device for adjusting the internal pressure ofsaid chamber so as to adjust its diametral expansion.

PRIOR ART

For patients suffering from extremely severe obesity (morbid obesity),i.e. for patients whose weight exceeds the ideal weight by at least 50kilograms, for example, it is absolutely essential to operate surgicallyon such patients in order to avoid not only a series of health problemsthat stem from such obesity, but also to avoid certain and imminentdeath of such patients.

It is accepted that patients suffering morbid obesity have lifeexpectancy that is significantly reduced, by at least ten to fifteenyears, while also giving rise to severe psychological problems.Furthermore, a whole series of associated health phenomena are involved,having an effect on the appearance of cardiovascular diseasehypertension, diabetes, and severe arthritis, in particular.

It has also been observed that treatment based on a severe diet combinedwith a series of physical exercises associated with a change inbehavior, in particular eating behavior, are relatively ineffective insuch cases of morbid obesity, even though such methods of treatment arethe most healthy.

That is why effective long-term treatment of morbid obesity can involvesurgical treatment.

In general, surgical treatment techniques can be divided into thosewhich cause food to be absorbed poorly, i.e. shortening the conventionalpath followed by food and digestive juices, and techniques that make useof gastric restriction, i.e. reducing the size of the stomach.

By way of example, surgical techniques that rely on poor absorption arethose that imply a technique of bypassing the small intestine or those,which separate the paths followed by food and digestive juices. Thebypass surgical technique gives rise to severe complications, such thatthat technique is now used only very rarely. The surgical techniquewhereby the path followed by the alimentary bolus is separated from thatof the digestive juices does not give rise to particular complications,but it does require major surgery, and in particular it implies partialgastrectomy.

That is why present trends are towards using surgical techniques thatimplement gastric restriction to reduce food intake.

In conventional manner, such techniques make use of gastroplasty ringsimplanted around the stomach to reduce its size and the diameter of itspassage (stoma).

Most known gastroplasty devices, for example the device described inU.S. Pat. No. 5,074,868, make use of a flexible strip made of elastomermaterial that is implanted around the stomach and then tightened andclosed to form a loop of fixed diameter by means of a closure system.The body of the flexible strip includes a variable volume compressioncavity or chamber that is connected by an adjustment catheter to adevice for adjusting the internal pressure of the chamber so as to varythe internal diameter of the loop and thus modify or adjust the diameterof the stoma by injecting or extracting a volume of liquid into or fromthe chamber. Such an operation of adjusting the inside diameter of thering is performed by means of conventional control devices including aminiature unit implanted directly beneath the skin of the patient andprovided with a self-closing membrane through which the doctor injectsor withdraws liquid by means of a syringe.

Utility model DE-G-90 14048 describes a partially annular systemspecifically designed and adapted to totally closing blood vessels, andits teaching is not directly transposable to compressing the stomachwhich must be done under full control.

The closure system of U.S. Pat. No. 5,075,868 makes use of suture threadfor suturing together the two strands of the flexible strip constitutingthe ring.

Such a device generally gives satisfaction, but like most known systemsit suffers from drawbacks associated essentially with the difficulty ofany surgical operation that may need to be performed after thegastroplasty implant has been into place. In spite of the possibility ofmodifying the diameter of the ring to some extent without a surgicaloperation by means of the above-mentioned miniature unit, it turns outthat implanting such gastric implants can be accompanied by phenomena ofintolerance, e.g. can be accompanied by vomiting, associating with thediameter of the stoma being reduced excessively, or they can beassociated with the implant being ineffective in its action because thediameter of the stoma is too large, or indeed they can be associatedmerely with local or general inflammation or infection or discomfort.

That is why it is often necessary to operate surgically again either torelieve the patient or to modify or change a previously implantedgastroplasty ring. Such surgical operations are particularly difficultand further require the surgeon to cut either the ring, or as in thecase of U.S. Pat. No. 5,074,868, the suture thread so as to open thering completely and then change it or replace it.

Such operations are awkward to perform, poorly tolerated by the patient,and expensive, particularly in that they imply the destruction of animplant and its replacement. In addition, in the case of U.S. Pat. No.5,074,868, the device for assisting in cutting the suture makes thesurgical implant relatively complex to manufacture and make up, withoutgenuinely providing much real help during the operation.

SUMMARY OF THE INVENTION

Consequently, the object given to the invention is to propose a novelgastroplasty ring making it possible to remedy the various drawbacksmentioned above and capable of facilitating any subsequent surgicaloperations after the implant has been implanted, without requiring theimplant to be replaced, and with the implant in any event being ofparticularly simple design that is easy to make.

Another object of the invention is to propose a novel gastroplasty ringcapable in simple and reliable manner of reversibly closing the loopthat constitutes the ring.

Another object of the invention is to propose a novel gastroplasty ringsuitable for providing simple and reliable means for adapting thediameter of the ring to each particular surgical situation.

Another object of the invention is to propose a novel gastroplasty ringsuitable for presenting a plurality of implantation diameters.

Another object of the invention is to propose a novel gastroplasty ringmaking it possible to reduce the discomfort felt by the patient whilenevertheless being firmly held in place by the loop.

Another object of the invention is to propose a novel gastroplasty ringthat is particularly easy to manufacture while also providing excellentgeneral strength.

The objects given to the invention are achieved by means of agastroplasty ring formed by a flexible strip suitable towards its twoends for being closed around the stomach by a closure system so as toreduce the diameter of the opening of the stoma, said strip having anannular compression chamber of adjustable volume and of substantiallyconstant section connected by an adjustment catheter to a device foradjusting the internal pressure in said chamber so as to adjust itsdiametral expansion, the ring being characterized in that the closuresystem includes means for reversibly locking and loosening the ring,said means comprising male means and female means forming a cavity inwhich or against which the male means can expand and become locked inreversible manner, thus making it possible, starting from the positionin which the diameter of the ring is locked, to release the diameter ofthe ring momentarily by relative displacement between the two ends,while nevertheless continuously forming a closed loop around thestomach.

BRIEF SUMMARY OF THE DRAWINGS

Other objects and advantages of the invention will appear better onreading the following description and from the accompanying drawingsgiven purely for illustration and information, in which:

FIG. 1 is a diagrammatic perspective view of an embodiment of agastroplasty ring of the invention shown in the closed position;

FIG. 2 is a diagrammatic perspective view of an embodiment of agastroplasty ring of the invention in the open position prior to beingimplanted;

FIG. 3 is a fragmentary cross-section view showing a detail of thesection of the gastroplasty ring of the invention;

FIG. 4 is a perspective view showing a variant embodiment of thegastroplasty ring of the invention; and

FIG. 5 is a fragmentary section view showing an implementation detail ofa variant of a gastroplasty ring of the invention.

BEST MANNER OF PERFORMING THE INVENTION

FIGS. 1 and 2 show a preferred embodiment of a gastroplasty ring of theinvention formed by a flexible strip 1 made, for example, bythermoforming an elastomer material for surgical use. The strip 1defines an internal compression chamber 2 of substantially constantsection that preferably extends substantially over its entire length,the chamber being defined by the walls 3 of the flexible strip 1 and bytwo end zones 5 and 5′. In its position when implanted around thestomach of a patient, as shown in FIG. 1, the compression chamber 2 thusforms an annular compression chamber of section and profile that areadapted to avoid forming any pinch zones that could nip the walls of thestomach. This implies in particular that it has a contact surface withthe stomach that is continuous and uniform and that an annularcompression zone is formed that is almost perfect, excluding inparticular any droplet shape that might damage cellular tissue.

As is well known in the prior art, the compression chamber 2 defines aclosed volume inside the gastroplasty ring, for the purpose of forming avolume that is adjustable so as to adjust the diametral expansion of thering while it is in place in order to adapt it to each particularsurgical situation.

In conventional manner, the diametral expansion of the gastroplasty ringof the invention is adjusted by an adjustment catheter 4 formed by atubular element of elastomer material extending the free end 5 of thecompression chamber 2 so as to connect said chamber to a device 6 foradjusting the internal pressure of said chamber.

As is well known to the person skilled in the art, the adjustment device6 can be formed by a miniature unit 7 that is implanted beneath the skinof the patient. By way of example, the miniature unit 7 has aself-sealing membrane 8 on top for being pierced by a syringe so as toinject or withdraw a certain quantity of fluid (e.g. distilled water)for the purpose of varying the volume of the compression chamber 2, toadjust the volume of the chamber and thus obtain the desired internaldiameter for the ring. Since such a device is well known to the personskilled in the art, it is not described in greater detail herein.

The gastroplasty ring of the invention also has a closure systemenabling it to be closed and serving to hold the gastroplasty ringlooped in position around the stomach.

According to an important characteristic of the invention, the closuresystem of the invention includes means for reversibly locking andloosening the ring, making it possible starting from the closed positionshown in FIG. 1 where the ring is looped with a locked diameter, torelease its diameter momentarily by allowing the two ends of the ring tomove relative to each other, while nevertheless continuously forming aclosed loop around the stomach.

Providing this technical function makes it possible to reduce theseverity and the extent of any subsequent surgical operations after animplant has been put into place by avoiding the need to section anddestroy the installed gastroplasty ring, with this function making itpossible to leave the ring in place while merely momentarily increasingits diameter without destroying the loop of the ring, thus making itpossible subsequently to retighten the ring so as to return it to theclosed position as shown in FIG. 1.

In a preferred variant of the invention, as shown in FIGS. 1 to 3, thegastroplasty ring of the invention includes a closure system thatcomprises:

-   -   male means and female means secured to the strip 1, e.g.        situated substantially in the vicinity of respective ones of the        two ends 5 and 5′, the male and female means being mounted on        the strip, i.e. extending its two ends 5 and 5′ so that during        mutual connection thereof the strip 1 is closed to form a loop;        and    -   reversible locking and loosening means are mounted on the male        means so as to be suitable for sliding in the female means 10        between a locking position and at least one loosened position,        while nevertheless enabling the loop to be maintained.

The preferred embodiment shown in the figures has female means in theform of an eyelet 10 provided at the periphery of the strip 1 in aposition adjacent to the end 5. The male means is formed by aninflatable catheter 11 made of biocompatible elastomer material forthreading through the eyelet 10 in the closed ring position and also forserving as guide means.

The reversible locking and loosening means are connected to theinflation catheter 11 and comprise a deformable zone 12 suitable forforming a projection 13 when the pressure inside the inflation catheter11 is increased, said projection 13 bearing in or against the femalemeans 10 to lock the ring in the closed position. The projection 13returns to its rest shape if the pressure inside the inflation catheter11 returns to normal, thereby allowing the said catheter to slide and beguided freely through the eyelet 10, thus loosening the loop.

The reversible locking and loosening means are advantageously formed onthe inflation catheter 11 (FIGS. 1, 2, 5) and are intended to co-operatewith the eyelet 10 so that when the eyelet 10 is connected to theinflation catheter 11, the ring is locked reversibly and is capable ofbeing loosened.

In a particularly advantageous version of the invention, the reversibledeformation zone 12 is formed by at least one zone 13 of weaknesssuitable firstly for locally forming a projection in the event of thepressure inside the inflation catheter 11 increasing, said projectionthen bearing in or against the eyelet 10 to lock the ring in the closedposition, and suitable secondly for returning to its rest position whichthen corresponds substantially to the normal diameter of the catheter 11when pressure returns to normal so as to allow the inflatable catheter11 to slide freely in the eyelet 10, thereby allowing the loop to beloosened. The weak zone 13 can extend over the entire peripheral sectionof the catheter 11 to form a bulb, or over a fraction only thereof so asto form a simple projecting dome.

Advantageously, the deformable zone 12 can be constituted by a sectionof the inflation catheter 11 having elastomer material constituting theinflatable catheter 11 presenting hardness which is locally less thanthe general hardness of the inflation catheter 11. Under suchcircumstances, the inflation catheter 11 is connected to an externaldevice for being pressurized by means of a fluid (air or liquid), andthe zone 12 tends to form a balloon 13 of diameter greater than thediameter of the eyelet 10, thereby locking the diameter of the ring.

Naturally, and in a variant, a gastroplasty ring of the invention couldhave a plurality of weak zones 12 spaced apart in optionally regularmanner along the inflation catheter 11 to make up a gastroplasty ringcapable of occupying a plurality of fixed diameters when in position.Advantageously, the inflation catheter 11 has two weak zones 12 and 12′.

In this preferred embodiment, the locking and loosening means make useof fluid means (pneumatic or hydraulic, air, fluid, or liquid, forexample) that perform the reversible locking and loosening function.

Advantageously, the flexible strip 1 is provided at one end, e.g. at itsend 5′ opposite its end 5, with a hollow sleeve 15 extending theflexible strip 1, which hollow sleeve 15 has one end 16 of theinflatable catheter 11 fixed thereto. The hollow sleeve 15 also has anopening 17 provided in one of its face (preferably an outside face) soas to enable the other end 5 of the flexible strip 1 to be inserted intosaid sleeve in the closed position with the adjustment catheter 11 thenpassing through the opening 17 so as to loop the ring (FIG. 2). Thisstructural disposition ensures that closure is reliable and longlasting, while also enabling the compression chamber 2 to extend overthe entire perimeter over which the stomach is constrained.

As already described above, the eyelet 10 is advantageously placed at adistance from the end 5 of the strip so as to create a free portion ofthe compression chamber 2 for insertion into the hollow sleeve 15 inorder to enable the ring to be put into place in its looped position.

Advantageously, the flexible strip 1, the compression chamber 2, and thefemale means 10 form a single piece made out of the same elastomerplastic material, the adjustment catheter 4 and the inflation catheter11 which are independent of each other being subsequently heat-sealedthereto.

FIG. 5 shows a variant embodiment which differs from that of FIGS. 1 to3 mainly in the female means 10, which are of a geometricalconfiguration for improving locking. In this variant, the eyelet 10includes or is formed by a through cavity 10 b in which the projection13 or the balloon can expand and become reversibly locked in positiondepending on the pressure of the fluid. The cavity 10 b can be situatedto extend continuously from the annular section of the chamber 2 so asto form a ring that is regular and formed in full or in part by thehollow sleeve 15 or in line therewith on the other end of the ring.

FIG. 4 shows another variant which differs from the preceding variantonly in the configuration of the deformable zone 12. This zone is formedby a substantially oblong bag 12 a secured to the flexible strip 1, e.g.extending the end 5′ and fixed thereto. The inflation catheter 11extends the bag 12 a and is connected to the end portion thereof. Whilethe ring is being closed, the catheter 11 and then the bag 12 a arethreaded through the eyelet 10, with the bag 12 a (or the major fractionof its length) then projecting beyond the eyelet 10. When the inflationcatheter 11 is pressurized, the bag 12 a inflates as represented bydashed lines in FIG. 4, thus locking and closing the ring.

Making a gastroplasty ring as a single piece simplifies the method ofmanufacturing the ring and makes it possible to obtain a ring thatavoids any risk of coming apart over time.

While the ring of the invention is being put into place around thestomach, it is in the position as shown in FIG. 2. The adjustment device6 is initially disconnected and the surgeon passes the adjustmentcatheter 4 through the opening 17 so as to insert the end 5 in thehollow sleeve 15 (FIG. 1). Thereafter, the surgeon can use an inflationdevice (not shown in the figures) connected to the inflation catheter 11to lock the ring in position after making sure that the weak zone 12corresponding to the diameter desired for the implant is properlypositioned relative to the eyelet 10. Thereafter, the surgeon can adjustthe inside diameter of the ring by injecting or withdrawing theappropriate quantity of liquid by means of the adjustment device 6.

In the event of a subsequent surgical operation, the gastroplasty ringof the invention makes it possible to limit the operation to examiningthe outside surface of the implant in position by celioscopy orlaparoscopy, merely using a camera for optical inspection. Ifcircumstances require it, it is possible initially, merely bycelioscopy, to reduce the pressure in the inflation catheter 11, therebyreleasing the balloon 13 and allowing the inflation catheter 11 to slidethrough the eyelet 10 given that this catheter is of sufficient length.Such sliding is accompanied by momentary and partial loosening of thering without it being necessary to perform major surgery on the patient.Thereafter, still merely by laparoscopic examination and intervention,it is possible to reclose and relock the ring in the closed position invery simple manner since the loop of the ring has never been undone.

SUSCEPTIBILITY OF INDUSTRIAL APPLICATION

The industrial application of the invention lies in designing and usinggastroplasty rings.

1. A gastroplasty ring formed by flexible strip (1) suitable towards itstwo ends (5, 5′) for being close around the stomach by a closure system(10, 10 b, 11, 12, 12′, 13) so as to reduce the diameter of the openingof the stoma, said strip having an annular compression chamber (2) ofadjustable volume and of substantially constant section connected by anadjustment catheter (4) to a device (6) for adjusting the internalpressure in said chamber so as adjust its diametral expansion, the ringbeing characterized in that the closure system (10, 10 b, 11, 12, 12′,13 ) includes means (10, 10 b, 12, 12′, 13) for reversibly locking andloosening the ring, said means comprising male means (11) and femalemeans (10, 10 b) forming a cavity in which or against which the malemeans (11) can expand and become locked in reversible manner, thusmaking it possible, starting from the position in which the diameter ofthe ring is locked, to release the diameter of the ring momentarily byrelative displacement between the two ends (5, 5′), while neverthelesscontinuously forming a closed loop around the stomach.
 2. A ringaccording to claim 1, characterized in that the locking and looseningmeans make use of a fluid means selected from the group comprising ofair and a liquid.
 3. A ring according to claim 1, characterized in thatin the closure system (10-13 ): the male means (11) and the female means(10) are secured to the strip (1) and are mounted thereon to extend itstwo ends (5, 5′) in such a manner that when they are mutually connected,the strip (1) is closed to form a loop; and the reversible locking andloosening means (12, 12′, 13) are mounted on the male means (11) and aresuitable for sliding in the female means (10) between a locking positionand a loosening position.
 4. A ring according to claim 1, characterizedin that the female means is formed by an eyelet (10, 10 b), the malemeans is formed by an inflatable catheter (11) for inflating through theeyelet (10, 10 b), the reversible locking and loosening means beingconnected to the catheter (11) and including at least one deformablezone (12, 12′) suitable firstly for forming a local projection (13) inthe event of the pressure inside the catheter increasing, saidprojection hearing against the eyelet (10) to lock the ring in theclosed position, and secondly for returning to its rest shape in theevent of a return to normal pressure so us to allow the inflatablecatheter (11) to slide freely in the eyelet (10, 10 b) and loosen theloop.
 5. A ring according to claim 4, characterized in that thedeformable zone (12, 12′) is a weak zone formed in the inflationcatheter.
 6. A ring according to claim 5, characterized in that thedeformable zone (12) is formed by a bag (12 a) extending the end (5′) ofthe flexible strip (1) and to which the inflation catheter (11) isconnected.
 7. A ring according to claim 4, characterized in that theinflatable catheter (11) has two weak zones ( 12, 12′) spaced apartalong said catheter.
 8. A ring according to claim 4, characterized inthat the flexible strip (1) is provided at one end (5′) with a hollowsleeve (15) to which one end (16) of the inflatable catheter (11) isfixed, said sleeve having an opening (17) so that the other end (5) ofthe strip (1) can be inserted into the sleeve (15) with the adjustmentcatheter (4) then passing through the opening (17) so as to loop thering.
 9. A ring according to claim 4, characterized in that theinflatable catheter (11) is connected to a device for pressurizing itand depressurizing it.
 10. A ring according to claim 8, characterized inthat the eyelet (10) is placed at a distance from one end (5) of thestrip (1) so as to create a free portion of the chamber (2) suitable forbeing inserted in the hollow sleeve.
 11. A ring according to claim 1,characterized in that the flexible strip (1), the compression chamber(2), and the female means (10, 10 b) form a single piece made from thesame plastics material.
 12. A ring according to claim 1, characterizedin that the compression chamber (2) extends over the entire periphery ofthe ring.